21412740 has 48 divisors (see below), whose sum is σ = 60342912. Its totient is φ = 5673216.

The previous prime is 21412739. The next prime is 21412789. The reversal of 21412740 is 4721412.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8952 + ... + 11088.

It is an arithmetic number, because the mean of its divisors is an integer number (1257144).

Almost surely, 2^21412740 is an apocalyptic number.

21412740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21412740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30171456).

21412740 is an abundant number, since it is smaller than the sum of its proper divisors (38930172).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21412740 is a wasteful number, since it uses less digits than its factorization.

21412740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2316 (or 2314 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 21412740 is about 4627.3901931867. The cubic root of 21412740 is about 277.6881930968.

The spelling of 21412740 in words is "twenty-one million, four hundred twelve thousand, seven hundred forty".